What to wear to prom?

I'm 16 and my year 11 prom is coming up in the next few months and it seems like everyone has already bought their dress...i promised my self that i would loose weight before prom, due to my anti depressents making my go from an average size 14 to a much larger size 18-20. sadly did not succeed in my goal but still really want to go to prom. I gained weight more around my tummy area than anywhere else. My friends tell me they would love to have my because due to the weight gain they grew too. lol. so if i could find a dress that could excentuate my best bits and hide my not so good bits then that would be fab. if anyone has any ideas for a dress that could suit the fuller figure please tell!!!!!